Argument Parsing

- Obsoleted Command::exectute  'commandLine' argument.  It is worse
  than unnecessary, it is an uncategorized raw argument string, which
  is only really useful for the 'execute' command, which itself now
  calls Arguments::combine to reconstruct the command line string.

src/commands/CmdInstall.cpp

@@ -47,7 +47,7 @@ CmdInstall::CmdInstall ()
 //   Generate UUID
 //   Call the "install" function once, store results in rc:
 //     extension.<uuid>=<JSON>
-int CmdInstall::execute (const std::string&, std::string&)
+int CmdInstall::execute (std::string&)
 {
   return 1;
 }